Hi,
I am Gal from the Wix App
As Forum is indeed supported in the Wix App, it must have been related to the member view customization.
In order to add it to the member view, please enter the customization flow (you can do it by simply hit the logo square) and add forum section to a new tab or existing tab.
In the dashboard it should appear anyway.
Let me know if that solves your issue and if not I’ll be happy to further assist
Gal